Various medicine packaging apparatuses have been provided which prepare continuous medicine bags or dose packages by packaging medicine such as tablet and powdered medicines per dose (as one medicine bags) based on prescriptions. Some of these devices use package sheet rolls on which long and narrow package sheets previously folded into two in the longitudinal direction is wound. Generally, in a packaging section of this kind of medicine packaging apparatus, a package sheet is fed from the roll, and required information is printed thereon by a printing section. The package sheet is then developed or unfolded from the folded state to be opened, and a nozzle section of a hopper is inserted into the opening to introduce one dose of medicine therein. Next, the package sheet is sealed (heat-sealed) in a heat sealing section so that the medicine is enclosed (see, e.g., JP 2004-189336 A, JP 2004-284663, JP 2004-238026 A and JP 2002-19737 A).
Upon first startup of the medicine packaging apparatus or at the time of roll replacement, it is necessary to routing a package sheet unrolled from the roll to the heat sealing section through the nozzle section of the hopper and the printing section before starting medicine packaging operation. In other words, in the roll replacement operation and the like, a length of the package sheet from the printing section to the heat sealing section (the length generally equivalent to 5 to 6 packages) functions only for the routing, i.e., the length is not used for medicine packaging and therefore should be discarded, which is not desirable in view of cost. Moreover, the long path of the package sheet from the printing section to the heat sealing section hinders downsizing of the medicine packaging apparatus. Accordingly, reduction in path length from the printing section to the heat sealing section can eliminate a waste of the package sheet caused by the roll replacement and the like and achieve downsizing of the apparatus. However, merely shortening the path cannot prevent generation of wrinkles on the package sheet in the heat sealing section. Generation of the wrinkles is particularly notable when the heat sealing section employs a method of heat-sealing the package sheet by passing the package sheet between a pair of heater rollers.
With reference to FIGS. 45 and 46, a two-folded package sheet 1100 is expanded into V shape by a unfolding guide 1106, and reaches a heating roller 1102 of a heat sealing section via a nozzle section 1101 of a hopper. The heater roller 102 has a horizontal seal 1103 which seals an opening edge of the package sheet 1100 in the longitudinal direction, and a vertical seal 1104 which seals the package sheet 1100 crosswise from the opening edge to the fold of the package sheet 1100. If the tension applied to both the sides of the two-folded sheet 1100 is unbalanced during application of the vertical seal 1104, one side of the two-folded sheets 1100 sags against the other side, which tends to generate wrinkles 1105 extending in the longitudinal direction near the horizontal seal 1103. The wrinkles 1105 are assumed to be attributed to such causes as a bulge of the package sheet 1100 generated in putting medicine therein and a difference of tension between the portions of the package sheet 1100 where the horizontal seal 1103 is formed and where the vertical seal 1104 is formed. Such wrinkles 1105 result in poor airtightness due to sealing and thereby causes mixture (contamination) of medicine between adjacent prescriptions.
JP 2004-189336 A and JP 2004-284663 A disclose a unfolding guide 1106 in the shape of a triangular plate with a constant thickness and a unfolding guide 1106 constituted of a plurality of flat planes and having an outline of a generally triangular pyramid shape. However, if the unfolding guides 1106 in such shapes are employed and placed in the vicinity of the printing section to shorten the path length from the printing section to the heat sealing section, then the above-mentioned wrinkles 1105 are unavoidably generated on the package sheet 1100.
The medicine packaging apparatus of this kind also has a problem in which medicine (powdered medicine in particular) fed from a powdered medicine supply unit or a tablet supply unit to the packaging unit adheres to the hopper and remains there to cause contamination. As a solution to the residual medicine, a technique is known which smoothes the movement of the medicine within the hopper by a solenoid driving mechanism intermittently striking the hopper so as to apply impact thereto. However, the intermittent striking of the hopper cannot necessarily achieve effective prevention of adhesion of the medicine to the hopper. Moreover, the sound generated when a striking mechanism strikes the hopper is unpleasant for operators, and the striking sound may be misunderstood by the operators to be caused by failure of the apparatus. For example, in small-scale dispensing pharmacies, the striking sound of the hopper may resound through the room and may make not only the operators but also patients unpleasant. In order to minimize the striking time of the hopper in consideration of the displeasure given to the patients, striking by the solenoid mechanism is generally performed for a short period of time after the medicine is discharged from the nozzle section on the lower side of the hopper. However, the striking for such a very short time is not desirable in view of effective prevention of the residual medicine. Thus, the conventionally known medicine devices of this kind cannot achieve effective prevention of the residual medicine in the hopper while reducing the displeasure given to operators and patients.